1. Field of Invention
The present invention relates to an electrolytic reduction module, and more particularly to a water body electrolytic reduction module having a self-generating capability.
2. Related Art
In the general transportation or storage process of a water body such as industrial water or domestic water, large amounts of substances harmful to human body such as bacteria, virus, or other microorganisms deteriorating the water quality exist due to the contamination of inorganic or organic substances in the transportation or storage environment. Taking common domestic water such as tap water, spring water, ground water, or well water for example, the domestic water is first transported from a water source through a transportation pipeline and stored in a reservoir, and then output from a water transmission pipeline connected to the reservoir to a water use end.
In order to make the domestic water reach a standard of suitability for use when being output to the water use end, a chemical drug (a bactericide or scale remover) is usually added to the water body in the reservoir periodically. For example, sodium hypochlorite is put into or chlorine gas is let into the water body, and the sodium hypochlorite or chlorine gas is oxidized in the water body, so that oxidizing substances such as free residual chlorine (HOCl+OCl−) exist in the water body, thereby ensuring no bacteria breeding or follow-up harm for the water body before the use of the water use end. Although the free residual chlorine has sterilization and disinfection effect in the water body, a concentration of the free residual chlorine contained in the water body as high as about 2-3 ppm (mg/L) deteriorates the quality of the water body and gives the user a pungent odor specific to the free residual chlorine. Therefore, in consideration of the feeling of most people and the disinfection efficacy of the residual dose of the free residual chlorine, the World Health Organization (WHO) has recommended a concentration of free residual chlorine below 0.1 ppm as a reference stipulated in view of potability, and advised different countries to make adjustment by themselves according to different national conditions.
However, free residual chlorine standards stipulated in some countries are still above such stipulated reference. Moreover, in some parts or areas exposed to heavy rains, due to water source contamination, an average concentration of free residual chlorine contained in water bodies is increased by around 10 times, which is a high risk in life for human contacting and drinking despite the guarantee that the water bodies have a sterile quality. In addition, according to demonstrations of scientific research, free residual chlorine having high oxidizability may influence the human body through not only food intake but also skin absorption. To a slight extent, free residual chlorine may be acidified and destroy the protein in hair and skin so as to damage the hair and skin; to a serious extent, free residual chlorine may cause chronic diseases such as heart diseases, arteriosclerosis, and hypertension, allergy, and other symptoms to the human body.
In view of this, although an appropriate amount of free residual chlorine is really needed in the water body to achieve the effect of sterilization and disinfection on the water body, the concentration of the free residual chlorine and other oxidizing substances contained in the water body must be reduced to the lowest or the free residual chlorine and other oxidizing substances contained in the water body must be removed from the water body as much as possible when the water body is transported to the water use end through the water transportation pipeline, so as to avoid harm to the human body.
In current methods for removing the free residual chlorine or other oxidizing substances in the water body, a filtering (or water purification) device is usually installed between the reservoir and the water use end, so that a water body containing a oxidizing substances (for example, free residual chlorine) first circulates to the filtering device and the oxidizing substances are adsorbed by adsorbents filled in the filtering device, for example, the oxidizing substances are adsorbed by or reacted with porous ceramic balls, activated carbon, or other chemical agents, so as to be removed from the water body.
However, in the use of the conventional filtering device, since the filtering device has a complex structure and occupies a certain volume, the filtering device can only be installed in some specific areas for use, for example, mostly installed in an accommodating space below a water tank in ordinary houses for filtering drinking water. Thus, the filtering device cannot be widely applied to other water transportation equipment due to the limitation of its own volume.
In addition, the adsorbents filled in the filtering device may contaminate the quality of the water body after long-term contact with the water body, and thus need to be replaced periodically. Moreover, an operating power supply must be provided additionally for smooth operation of the filtering device, so the use cost of the filtering device is increased greatly, and excessive energy consumption is caused.